The subject matter of this patent specification relates to the processing and display of breast ultrasound information as described, for example, in the commonly assigned US 2003/0007598A1 and US 2003/0212327A1, each of which is incorporated by reference herein. The subject matter of this patent specification also relates to the processing and display of breast ultrasound information acquired according to the commonly assigned U.S. Prov. Ser. No. 60/629,007 filed Nov. 17, 2004, and U.S. Ser. No. 10/997.283 filed Nov. 23, 2005, each of which is incorporated by reference herein.
In one or more of the above-referenced disclosures, there are presented convenient schemes for viewer navigation between (a) thick-slice images generated from a breast volume and (b) planar (“single-slice”) images for that breast volume, as well as navigation in the other direction from the planar images to the thick-slice images. Thus, for example, a viewer can click on a region of interest (ROI) in one of the thick-slice images, and the display will automatically show the appropriate corresponding planar images that pass through that ROI in the breast volume, and will also place markers thereon corresponding to that ROI. This is a valuable capability because the viewer is provided with multiple image presentations of the ROI without having to scan through the various images for corresponding ROIs, which can be a time-consuming and stamina-reducing task. Rather, the viewer simply clicks on the ROI on the image being examined, and that location is automatically “navigated to” and highlighted by the workstation display system in the other views. Generally speaking, such automated navigation between views is not problematic when there is a single ultrasound volume for each breast, because the absolute location of the ROI within the breast becomes known as soon as the viewer clicks on the selected point.
It has been found desirable in many instances to obtain multiple volumetric ultrasound scans of the same breast during the same session. With reference to FIGS. 28-32 infra, the multiple volumetric ultrasound scans can be head-on scans taken at differing positions or orientations, each of the scans being taken while a taut surface compresses the breast in a generally chestward direction and an ultrasound probe is swept thereacross. In other cases, there may be scans taken while the breast is compressed along differing mammographic planes such as the CC or MLO planes, as iconically represented, for example, by the body marker icons 1202, 1204, and 1206 of FIG. 12 infra.
The use of multiple volumetric scans can overcome certain disadvantages associated with of single-volumetric scan scenarios. In particular, for any particular volumetric ultrasound scan, there can be shadowing or other obfuscations of interesting tissue structures because of the presence of other tissue structures that are “in the way” during the scanning process. When there is only a single volumetric scan available, there is generally no way for the viewer to know what structures are behind or underneath the obfuscating structures. However, when there are multiple volumetric ultrasound scans available that were taken from different positions/directions, the viewer can consult a second ultrasound volume to better see the obfuscated structure.
It would be desirable to streamline the process of viewing additional ultrasonic volumes by providing for automated navigation between a first ultrasonic volume of a breast acquired during a first volumetric scan thereof and a second ultrasonic volume of the same breast taken during a second volumetric scan thereof, the first and second volumetric scans having been taken at differing positions and/or orientations.
Volumetric ultrasound scanning of the breast has been proposed as a complementary modality for breast cancer screening as described, for example, in the commonly assigned US 2003/007598A1 published Jan. 9, 2003, which is incorporated by reference herein. Whereas a conventional two-dimensional x-ray mammogram only detects a summation of the x-ray opacity of individual slices of breast tissue over the entire breast, ultrasound can separately detect the sonographic properties of individual slices of breast tissue, and therefore may allow detection of breast lesions where x-ray mammography alone fails. Another well-known shortcoming of x-ray mammography practice is found in the case of dense-breasted women, including patients with high content of fibroglandular tissues in their breasts. Because fibroglandular tissues have higher x-ray absorption than the surrounding fatty tissues, portions of breasts with high fibroglandular tissue content are not well penetrated by x-rays and thus the resulting mammograms contain reduced information in areas where fibroglandular tissues reside.
The commonly assigned WO 2004/030523A2 published on Apr. 15, 2004, which is incorporated by reference herein, describes a full-field breast ultrasound (FFBU) scanning apparatus that compresses a breast along a standard mammographic view plane such as the craniocaudal (CC) plane, the mediolateral oblique (MLO) plane, etc., and ultrasonically scans the breast. A scanning surface comprises an at least partially conformable, substantially taut membrane or film sheet compressing one side of the breast. The other side of the breast is compressed by a compression plate, optionally with the aid of an inflatable air bladder. A transducer translation mechanism holds a transducer surface against an opposite side of the film sheet while translating the transducer thereacross to scan the breast. An irrigation system automatically maintains a continuous supply of coupling agent at an interface between the transducer surface and the film sheet as the transducer is translated.
The operation of the scanning apparatus described in WO 20041030523A2, supra, depends at least in part on the “pendulous” properties of the breast, that is, the ability of the breast to extend away from the chest wall onto the scanning surface for compression along the axial plane (for CC scan), coronal plane (for lateral scan), or other anti-coronal plane lying between the axial and coronal planes (e.g., for MLO scan). As used herein, the term anti-coronal plane refers to a plane that lies generally perpendicular to the coronal plane. As with conventional x-ray mammography, the presumption is made that most breasts will have such pendulous properties. While effective for a large portion of the population, problems arise for patients having smaller breasts without pendulous properties, because much of the diagnostically relevant breast tissue cannot extend outward over the scanning surface by a sufficient amount. Moreover, even for patients with pendulous breasts, there can be difficulty in imaging the tissue near the chest wall that does not extend onto the scanning surface.
One important quality a breast ultrasound scanning apparatus is ease of mechanical control and manipulation. Generally speaking, acquiring volumetric ultrasonic breast scans can be a highly patient-specific process, not only in view of the wide variety of breast sizes, shapes, and densities, but also in view of the wide variety of different patient body shapes near and around the breast area (e.g., shoulder contours, sternum contours, ribs contours, etc.) A scanning apparatus that is versatile and easily adaptable to the particular patient being scanned can therefore facilitate optimal acquisition of ultrasonic views of the breast volume. Moreover, ease of use can also positively affect the salability and commercial success of the scanning apparatus.
Accordingly, it would be desirable to provide a breast ultrasound scanning apparatus that is easy to mechanically control and manipulate for facilitating high-quality volumetric ultrasonic scans across a variety of different patients.
It would be further desirable to provide a breast ultrasound scanning system that is capable of accommodating small, non-pendulous breasts as well as pendulous breasts.
It would be further desirable to provide a breast ultrasound scanning apparatus that can achieve high-quality ultrasound imaging even near the chest wall of the patient.
It would be further desirable to provide such a breast ultrasound scanning apparatus that is comfortable for the patient, has a cost-efficient patient throughput rate, and that is cost-efficient to own even for smaller medical clinics.